Carton closing arrangement and method



April 16, 1968 D. E. BURT 3,377,768

I CARTON CLOSING ARRANGEMENT AND METHOD 5 Sheets-Sheet 1' 014mg Mag ATTORNEYS I INVENTOR D0 nccZcZl'ZBurZ B Q@ m w NQ mm An 9 m NJ a U f Ill v J N gm o R o I 1 D. E. BURT April 16, 1968 CARTON CLOSING ARRANGEMENT AND METHOD 5 Sheets-Sheet 2 Filed June 22, 1967 INVNTOR D O m M EBZLT't April 16, 1968 D. E. BURT CARTON CLOSING ARRANGEMENT AND METHOD 5 Sheets-Sheet 5 Filed June 22, 1967 INVENTOR Q B, J,

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CARTON CLOSING ARRANGEMENT AND METHOD Filed June 22, 1967 5 Sheets-Sheet 4 NB Q a \S 5* s i N 1 3* N g Q 8 12 M! g u 2: o q 7\ w 1% o 9 w 2" o W 5 1 8 W k g 5, g &? INVENTOR gg m DomZdEBari (0 g %W% 8. ATTORNEYS April 16, 1968 D. E. BURT 3,377,768

CARTON'CLOSING ARRANGEMENT AND METHOD Filed June 22, 1967 v 5 Sheets-Sheet 5 I" ll u ll 1 iii 234 agin -=2?? INVENTOR ATTORNEYS United States Patent 3,377,768 CARTON CLOSING ARRANGEMENT AND METHOD Donald E. Burt, Boston, Mass., assignor to Keyes Fibre Company, Waterville, Maine, a corporation of Maine Continuation-impart of application Ser. No. 391,663,

Aug. 24, 1964. This application June 22, 1967, Ser.

11 Claims. (Cl. 5338) ABSTRACT OF THE DISCLOSURE An arrangement and method for closing flexible, open topped cartons wherein lids are positioned across the tops of the side walls of container portions of cartons, and thereafter-glue is applied in a longitudinal zone where downwardly folded flanges of the lids will contact the carton side walls. Reaction forces are supplied to prevent lateral inward flexing of the side walls in response to gluesetting forces applied laterally to the outer edges of the lid flanges.

Cross-reference to related application This is a continuation-in-part of pending application Ser. No. 391,663, filed Aug. 24, 1964, now abandoned.

Background of the invention This invention relates to an arrangement and method for closing flexible cartons, and more particularly to machinery and methods for gluing in the closed condition cartons of the type having trough-shaped container portions including bottom walls attached to upstanding side walls and generally planar lids positionable across the tops of the side walls and including marginal flanges adapted to be folded downwardly.

Prior to the present invention, carton closing arrangements and methods have been proposed for handling a wide range of cartons, including proposals for gluing together bottom portions and lid portions to secure filled cartons in the closed condition. One problem, however, connected with such proposals is the inability to consistently insure an even coating of glue or other adhesive media on the portions of the cartons which are to be secured together. More specifically, considerable difficulty has heretofore been experienced in providing adequate forces to properly set the glue in a time sufliciently short for high volume mass production operations. Especially on flexible cartons made of molded pulp, thin plastic or other such material which are adapted to contain fragile articles such as eggs, light bulbs and the like, it is extremely diflicult to provide adequate glue-setting forces without damaging the fragile articles in the flexible container when it is recognized that considerable manufacturing tolerances are encountered in such containers which renders fixed force applying devices totally unreliable. With bulk packaging machines of the type disclosed in Gaubert Patent 2,993,319, the packaged contents are relied on to prevent inward flexing of the carton side walls while glue-setting forces are applied, However, with fragile articles this expedient cannot be utilized effectively.

Accordingly, it is an object of the present invention to provide carton closing machinery and methods wherein cartons may be secured together by suitable adhesive media to lock them in the closed condition.

Another object of the present invention is to provide carton closing machinery including novel reaction force supplying means adapted to cooperate with a glue-setting ice force applicator means to secure together cooperating pairs of flexible carton members.

Another object of the present invention is to provide carton closing machinery including means for insuring positive frictional drive engagement between cartons and a carton conveying member which compensates for pro duction tolerances in carton dimensions.

Summary of the invention In accordance with the present invention, an arrangement and method are provided for closing flexible, open topped cartons of the type having trough-shaped container portions including bottom walls attached to upstanding side walls and generally planar flexible lids positionable across the tops of the side walls. The lids include marginal flanges adapted to be folded downwardly to lie against the outside of the upper portion of the side walls.

The carton closing arrangement comprises a conveyor that engages the bottom walls of container portions for moving them along a longitudinal path past spaced carton closing machinery. This machinery operates to position lids across the tops of the container side walls so the marginal flanges protrude laterally beyond the side walls and also, to apply glue in a longitudinal pattern to the zone where the downwardly folded flanges lie against the side walls. After the glue is applied the flanges are downwardly folded to a position where they lie against the side walls and glue-setting forces are then applied laterally against the folded marginal flanges. The lids are flexed downwardly immediately adjacent the inside of the upper portion of the side walls whereby the downwardly flexed portions of the lids supply reaction forces to prevent lateral inward flexing of the, side walls while the glue-setting forces are being applied.

The lids are flexed downwardly by a longitudinally extending member which may comprise a reach of a belt conveyor adapted to travel at the speed of the passing cartons. The conveyor in the preferred embodiment is trained about a plurality of roller positioning devices one of which is power driven to generate a surface speed of the reach comparable to the speed of the conveyor that engages the bottom walls of the container portions.

The glue-setting forces may be applied by a pressure member mounted for limited lateral motion, with yieldable biasing means provided to normally urge the pressure member to the laterally inward extent of its limited motion. The pressure member advisably may comprise a roller arrangement mounted for free rotation on an axis positioned generally perpendicular to the direction in which the glue-setting forces are applied. Moreover, the glue can be applied by a head positioned to deposit a continuous ribbon of glue on the lower surface of the laterally protruding marginal flanges.

Additionally, the lids may be pre-secured to the upper portion of the side walls on one side of the container portions. Alternatively, separate lids may be positioned on the container portions and the lid flanges on each side of the container portion glued simultaneously to the side Walls of the container.

Brief description of the drawing Other objects and advantages of the present invention will become apparent to one skilled in the art from a reading of the following description in conjunction with the accompanying drawings wherein similar reference characters refer to similar parts and in which:

FIG. 1 is a side elevational view of a carton closing machine according to this invention;

FIG. 2 is a plan view of the machine of FIG. 1;

FIG. 3 is a transverse sectional view on line 33 of FIG. 1 with certain parts eliminated for purposes of clarity;

FIG. 4 is a transverse sectional view on line 44 of FIG. 1 with certain parts eliminated for purposes of clarity;

FIG. 5 is a fragmentary elevational view of the glue applying head;

FIG. 6 is a transverse sectional view on line 66 of FIG. 1 with certain parts eliminated for purposes of clarity;

FIG. 7 is a transverse sectional view on line 77 of FIG. 1 with certain parts eliminated for purposes of clarity;

FIG. 8 is a longitudinal sectional view on line 8-8 of FIG. 2 showing details of the carton hold-down arrangement;

FIG. 9 is a fragmentary transverse sectional view on line 99 of FIG. 8 showing the carton hold-down arrangement cooperating with a carton wherein the height dimension is on the small side of ordinarily encountered tolerances;

FIG. 10 is a fragmentary transverse sectional view similar to FIG. 9 showing the carton hold-down arrangement cooperating with a carton wherein the height dimension is on the large side of ordinarily encountered dimension tolerances;

FIG. 11 is a diagrammatic view of another carton closing machine according to this invention;

FIG. 12 is a transverse sectional view on line 12-12 of FIG. 11;

FIG. 13 is a transverse sectional view on line 1313 of FIG. 11;

FIG. 14 is a transverse sectional view on line 1414 of FIG. 11; and

FIG. 15 is a transverse sectional view on line 1515 of FIG. 11.

Detailed description of the invention Referring in more particularity to the drawings, the various embodiments of this invention are illustrated as modified to close a particular type of carton. The carton used purely for purposes of illustration may comprise a molded pulp egg carton 10 of the type described in detail in Wade Patent 3,129,866 issued Apr. 21, 1964. Such a. carton 10 comprises a trough-shaped container portion 12 including a bottom wall 14 attached to upstanding side walls 16 and 18. The side walls 16 and 18 are connected across their ends by transverse or end walls 20. The illustrated carton further includes a plurality of pockets 22 interrupting the bottom wall for individually positioning fragile articles such as eggs in two parallel rows of six eggs each. The tops of the side walls and transverse end walls extend to a height comparable to the longest dimension of eggs to be packaged therein, and the tops of these walls all lie in a common, essentially flat plane 24 generally parallel with the plane of the bottom wall 14 of the car-ton.

The carton 10 further includes a lid portion 26 of generally planar configuration which is positionable across the tops of the side walls in the flat plane 24. The lid 26 includes marginal flanges 28 and 30 along the two opposite longitudinal sides thereof. The marginal flanges 28 and 30 are adapted to be folded downwardly to lie against the outside of the upper portion of the side walls 16 and 18, respectively.

The bottom container portion 12 of the carton is well adapted for the safe packaging of fragile articles such as eggs because of the unitary and rigid nature of the upstanding side Walls which extend to the full height of the eggs. It can be appreciated, however, that the presence of fragile articles between the side Walls militates against such walls being subject to severe lateral inward forces before the lid is secured thereacross because such forces would tend to flex the side walls inwardly with possibly damaging results to the contents. After the planar lid is suitably secured atop the side walls, however, the lid creates a structurally rigid packaging unit which has high resistivity to such lateral forces, and thus makes a mer chandising package highly satisfactory for the shipment, storage, stacking, merchandising and other handling of fragile articles such as eggs.

At present, one preferred manner of utilizing such cartons involves pre-securing the lids 26 to the container portion 12. Thus, whether the lid is integrally formed as a flap type closure member, or whether the lid is a separate unit pre-secured at its marginal flange 30 to the upper portion of the side wall 18 by stapling, gluing or other well-known attaching arrangements, the cartons are shipped to the egg packager with the lids 26 forming part of the carton. The lids normally occupy a vertical plane when they are pre-secured to the container portion along one side. It will be obvious that such lids 26 may be folded about first longitudinal hinge lines 32 to position the planar portion of the lids horizontally across the tops of the carton side walls. Similarly, the opposite marginal flanges 28 may be folded downwardly about second longitudinal hinge lines 34 to position the flanges so that they will lie against the upper portion of the side walls 16. Advisably, the bottom container portions 12 are constructed of material such as molded pulp, and the lids 26 are constructed of material such as chipboard or light plastic. If desired, the hinge lines 32 and 34 may be pre-designated by means of creases, serrations, perforations or the like.

The closing machine 36 comprises a main framework 38 adapted to be mounted on the floor of an egg packaging room. A main conveyor means 40 is connected to engage bottom walls 14 of cartons for moving them along a longitudinal path past spaced closing means. The conveyor means 49 includes a belt conveyor 42 trained about an idler pulley 44 journaled in the framework 38 at one end thereof and about a drive pulley 46 journaled in the other end of the framework 38 in conventional fashion. A belt tightening arrangement 48 may be provided if desired to insure that the upper reach of the belt 42 advances cartons through the machine at a uniform rate.

A pair of guide rails 50 are positioned longitudinally adjacent opposite sides of the belt 42 to guide longitudinal travel of cartons along the predetermined path through the machine. At the entrance end of the machine, a stationary folding plow arrangement 52 is provided to engage the vertically extending pre-secured lids 26 of cartons, and fold them about their rear hinge line 32 to properly position them across the tops of the side walls of the container portions of the cartons. The folding plow or lid positioning means 52 folds the planar portions of the lids to the horizontal or closed position wherein the front marginal flanges 28 project laterally beyond the side walls 12 of the cartons.

Securing means 54 are connected to apply adhesive media such as glue in a longitudinal pattern to a zone where the downwardly folded flanges 28 will lie against the upper portion of the side Walls 16. Such a means comprises a glue head 56 including an applicator wheel 58 rotated in a vertical plane by a belt drive 60 driven from the main machine motivating system explained below. A guide 62 including a downwardly inclined entrance face 64 as well as a longitudinal recess 66 is adjustably secured as at 68 directly above the glue applicator wheel 58. Glue in the form of a continuous flexible rod 70 is supplied to the glue head 56 by means of a pair of toothed drive wheels 72 driven by belting 74 from the motivating system for the machine, explained below. A supply of rod glue 70 may be stored in a roll 76 suitably secured on a support 78 attached to the machine. The details of the glue applying head 56 per se form no part of the present invention, and the description will not be burdened with details thereof. However, it should be noted that the head 56 used for purposes of illustration includes heating elements (not shown) for melting glue 70 fed thereto, as well as a reservoir (not shown) for collecting the molten glue. A level maintaining device (not shown) including limit switch St) is connected to intermittently operate the gear advancing means 72 which controls the level of molten glue in the reservoir at a sutficient height that the glue applicator wheel 58, which rotates continuously, will always have a bead of glue on its periphery. The undercut groove 66 in the guide shoe 62 is provided so that this head of glue will not engage the lower surface of the hold-down shoe when cartons are not passing through the machine. Additionally, the trailing corner of the glue applying head 56 may be beveled as at 82 to insure that carton lids to which glue has been applied in a manner described below will not engage the corner thereof.

Longitudinally adjacent the glue applying means 54, a marginal flange fold-down member 84 is provided. This may comprise a stationary folding plow adapted to engage the upper surface of front marginal flanges 28 and rotate them downwardly about their longitudinal hinge lines 34 so that they lie against the upper portion of the front walls 16.

Means 86 positioned longitudinally adjacent the flange fold-down member 34 are connected to apply glue-setting forces laterally against the downwardly folded marginal flanges. A first pressure member 88 is pivoted on an axis 90 perpendicular to the direction in which the glue-setting force is applied. The pivot 94) for the roller 88 may be secured in a bifurcated frame 92 pivotally mounted as at 94 to the main framework of the machine to enable the roller pressure member 83 to partake of limited lateral motion relative to the cartons path. An arm 96 of the frame 92 extending oppositely beyond the pivot mounting 94 is biased by a compression spring 98 to normally urge the roller pressure member 88 to the inward limit of its lateral motion. Another pressure member taking the form of a bar 88 is located adjacent the cartons path of travel to hold the glued flange inwardly.

The carton closing machine illustrated in FIGS. ll0 further includes means ltltl connected to supply reaction forces to prevent laterally inward flexing of the side walls 16 while the glue-setting forces are being applied by the arrangement 86. Such means advisably includes a V belt 162 trained about an idler pulley 104 and a drive pulley 106. The idler pulley 104 is mounted on a shaft 103 secured in adjustable pillow blocks 116 on an inverted U frame 112 located above the longitudinal path followed by cartons passing through the machine. The drive pulley 196 is mounted on a drive shaft 114 journaled in the inverted U frame 112 at the other end thereof. A plurality of rollers 116 each secured as at 118 in the lower portion of the front side 1213 of the inverted U frame 112 are adapted to position the lower reach of the V belt 102 so that it engages the upper surface of the planar lids adjacent the fold-down hinge lines 34 with a force sufficient to flex the upper or horizontal surface of the lid slightly downwardly immediately adjacent or inside the upper portion of the front side walls 16 (FIG. '7). The presence of the lid portion pressing downwardly behind the upper portion of the side walls serves as a reaction force to resist the tendency of the glue-setting roller 88 to flex the side walls laterally inwardly.

The rear side 122 of the inverted U frame 112 includes means connected to insure positive frictional drive ongagement between the cartons and the conveyor means of the machine. This means comprises a second V belt 124- trained at one end about an idler pulley 126 mounted for rotation on the longitudinally adjustable shaft 168, and trained at the other end about a flanged drive pulley 12f mounted for rotary motion on the transverse drive shaft 114. A plurality of rollers 130 secured as at 132 to a vertically shiftable back-up member 134 are adapted to position the lower reach of the V belt 124 properly relative to cartons passing therebeneath through the machine. The back-up arrangement 134 includes an angle bar having at each end upstanding guide rods 136 including flanged heads 138 at their upper portions. The shanks 136 of the upstanding members are received for sliding motion in vertical bores 140 in a pair of blocks 142 secured to the inner rear side 122 of the inverted U frame 112. A coil spring 144 is compressed in a suitable bore 146 in each block 142 to generate downward motion of the roller frame bar 134 to the limit permitted by the heads138.

For motivating the above described machinery, a common drive source such as an electric motor 150 secured as at 152 to the framework 38 drives a rotary sprocket 154 through a gear reduction drive unit 156. A roller chain 158 is trained first about an idler sprocket 160 located above the inverted U frame 112, and thereafter is trained about a drive pulley 162 secured to the transverse shaft 114 for the pulleys 106 and 128 of the lid engaging belts. Thereafter, the chain 158 drives a suitable pulley connected with the drive 46 for the belt 42 of the main conveyor means 40. Thus, the upper lid engaging belts 102 and 124- are driven with a surface speed corresponding to the surface speed of the main conveyor belt 42.

For driving the glue applying arrangement, a roller chain 164 trained about a first sprocket 166 driven by the shaft for the conveyor pulley 46 in turn drives a second sprocket connected with a shaft 168 extending transversely of the machine. The other end of the shaft 168 includes a suitable pulley for imparting rotary drive motion to the belt 60, described above.

In operation, the carton closing arrangement of FIGS. l-lO may be driven continuously by the motivating arrangement powered by the electric motor 159. The glue applying wheel 58 and the lid engaging; belts 102 and 124 continue to run whether or not cartons are passing through the machine. Accordingly, the machine is suitable for mass production carton closing operations in an egg packaging or other carton filling operation. To describe the operation of the various components of the closing machine described above, the following description will trace the movement of one carton through the machine.

First, a carton 10 is fed to the conveyor 42 at the entrance end of the machine. The carton is moved by the conveyor means 40 and as guided by the side rails 50 past the first carton closing station which comprises the stationary folding plow 52. Since a pro-secured lid 26 initially occupies a vertical position as illustrated in FIG. 3, the folding plow 52 is engaged by the leading edge of the lid 26, and the lid is thereafter rotated downwardly about its rear hinge line 32 to position the planar portion of the lid horizontally across the tops of the side walls of the carton bottom. In this position, the marginal flange 28 extends laterally beyond the side walls 16 of the carton.

Thereafter, the carton 16 is conveyed by the belt 42 past the glue'applying station 54. The laterally extending marginal flange 28 is guided by the downwardly inclined entrance face 64 of the glue head shoe 62 to be carried across the upper surface of the rotating glue applicator wheel 58. This deposits glue on the lower surface of the marginal flange 28 in a longitudinal pattern which, with a smooth surface Wheel, may comprise a continuous longitudinal bead of glue 170.

Continued application of beads of glue to a number of carton flanges will lower the level of molten glue in the reservoir in the head 56. Automatic level sensing means then actuates the limit switch 80 to activate the gear drive 72 through appropriate clutch arrangements to advance more glue in the form of a continuous rod 70 to the heated reservoir from the supply 76 of glue. Accordingly, the continually running glue applicator wheel 58 constantly maintains a head of molten glue on the upper surface thereof ready for the next carton which is fed through the mahcine.

As the leading end of the marginal flange 28 passes beyond the glue-applying station 54 with the head of glue 170 on the lower surface thereof, the upper surface of the flange engages beneath the fold-down member 84. The fold-down member rotates the flange 28 about its hinge line 34 so that the flange is positioned against the upper portion of the side wall 16 of the carton.

As the carton is passing the flange folding plow 84, the planar portion of the lid comes beneath the lid engaging belts 102 and 124. The belt 102 as explained above is positioned at a fixed height correlated with the height of the side walls 16 and 18 of cartons to flex the upper planar surface slightly downwardly immediately inside the upper portion of the front side wall 16, as best seen in PEG. 7. This provides a reaction force to resist gluesetting forces applied by the roller 88 at the following station.

Additionally, the belt 124 engages the rear edge of the top 26 adjacent the hinge line 32. As illustrated in FIG. 9, this engagement insures that the carton is held in driving frictional engagement with the main conveyor 42. However, as can be appreciated with reference to FIG. 10, such cartons frequently may be encountered where the rear flange 32 is glued, stapled or otherwise secured to the upper portion of the rear wall 18 in a manner which places the rear hinge 32 abnormally spaced above the plane 24- in which the tops of the carton walls lie. When this type of carton or one which includes abnormally large eggs is presented to the machine, the backup bar 134 which includes the idler rollers 130 is raised against the compression springs 144 seated in the blocks 142 to permit passage of such cartons while still maintaining adequate downward pressure thereon.

As the carton passes beyond the flange folding station 84, the folded-down flange will be conveyed past the gluesetting station. Here, the compression spring 98 urges the roller 88 against the marginal flange 28 with a glue-setting force suificient to spread the glue, and the bar 88 maintains a glue-setting force sufficient to hold the glued members in contact to securely bond the flange to the upper portion of the front side wall 16. As noted above, the belt 102 acts to prevent inward flexing of the front side wall 16, which flexing would otherwise tend to damage eggs or other articles in the carton. Obviously, the belt 124 also acts to restrain lateral shifting of the cartons, and the belt 102 helps maintain driving contact between the bottom of the cartons and the conveyor belt 42.

Finally, the closed and glued carton is transported by the conveyor belts 42, 102, and 124 to the exit end of the machine. Thus, it will be appreciated that cartons may be fed through the machine in close end-to-end relationship or, if desired, may be fed at any randomly spaced intervals through the machine.

Additionally, it will be appreciated that the glue-applying, flap fold-down, and glue-setting stations described above for closing cartons with lids which are pre-secured at one edge may also be duplicated on the opposite side of the machine to cooperate with means which positions lids across the tops of filled container portions of cartons to glue both sides simultaneously. This is advantageous when the cartons and lids are supplied separately to the packager. Such a machine is illustrated at 200 in FIGS. 11-15.

The carton closing machine 200 comprises a main framework 202 adapted to be mounted on the floor of an egg packaging room in the same manner as the machine 36. A main conveyor means 204 is connected to engage the bottom walls 14 of the cartons for moving them along a predetermined longitudinal path past spaced closing means. The conveyor means 204 includes a conveyor belt 206 trained about an idler pulley 208 and a drive pulley 210. At the entrance of the machine an escapement mechanism or gate 212 is connected to position the container portions 12 of cartons 10 at spaced intervals on the main conveyor means 204. By properly controlling the movement of the escapement mechanism 212 the carton container portions 12 are positioned at equally spaced intervals along the belt conveyor 206, as explained more fully below.

A stop arm 214 positioned longitudinally adjacent the escapement mechanism 212 is provided for coordinating the forward travel of the container portion 12 with the remainder of the carton closing machinery 200. The stop arm 214 is pivotally mounted on the main framework 202 for transverse movement toward and away from the conveyor belt 206 and includes a forward stop block 216 adapted to prevent the carton container portion 12 from traveling along the conveyor belt 206 when the stop arm is in its blocking position. The pivotal movement of the stop arm 214 is controlled by a stop arm cam and follower arrangement, not shown.

Pusher elements 218 traveling at a speed comparable to the speed of the main conveyor means 204 are connected to assist the container portion 12 in its travel through the balance of the carton closing machinery 200. The pusher elements are connected to a roller chain 220 trained about an idler sprocket 222 and a drive sprocket 224. The idler sprocket 222 is journaled to the main framework 202 between the stop arm 214 and the escapement mechanism 212. The drive sprocket 224- is also journaled to the main framework 202 of the machinery at 226. A chain tensioning arrangement 228 may be provided to accurately tension the roller chain 220. As illustrated in FIG. 11, four pusher elements 218 are connected to the roller chain 220 and each pusher operates on a single carton to move it from the stop arm 214 through the balance of the closing means of the machinery 200.

Longitudinally adjacent the stop arm 214, a lid storage hopper 230 and a lid positioning unit 232 are provided for supplying a single planar lid 26 to each passing container portion 12. The carton lids 26 are dispensed singly from a vertical stack within the hopper 230 by the lid positioning unit 232. As explained more fully below, the lid positioner 232 dispenses a lid from the hopper 230 and positions it above the conveyor belt 206 of the conveyor arrangement 204-. When the stop arm 214 moves transversely away from the conveyor belt 206 to allow the detained carton container portion 12 to travel along the main conveyor means 204 a pusher element 218 engages the container end wall 20 to assist the belt conveyor in moving the container through the remainder of the machine. Upon entering the space beneath the lid positioner 232, the upper portion of the pusher element 218 contacts the dispensed lid 26 and both the container portion and lid emerge from beneath the hopper in correct alignment and proper registry.

As the cartons emerge from beneath the lid hopper 230, a pair of transversely spaced stationary folding plows 234 connected to the main framework 202 are provided for engaging the horizontally extending marginal flange portions of the lid 26 to fold them about their hinge lines 32 and 34.

Lid gluers 236 are connected to the main framework 202 on each side of the conveyor belt 206 to apply adhesive media such as glue in a longitudinal pattern in a zone where the downwardly folded marginal flanges 28 and 30 will lie against the upper portions of the side walls 16 and 18, respectively, of the carton container portion 12. Each lid gluer comprises a glue reservoir 238 and a glue head 240 including an applicator wheel 242 driven by belting from the main machine motivating system. The previously described folding plows 234 also function to bring the marginal flanges 28 and 30 into contact with the applicator wheels 242 of the glue heads 240.

As shown in FIG. 13, the stationary folding plows 234 are inwardly inclined toward each other for engaging the upper surface of the marginal flanges 28 and 30 and rotating them downwardly about their respective longitudinal hinge lines so that they lie against the upper portions of the side walls 16 and 18 of the container portion 12.

Glue-setting units 244 positioned on each side of the conveyor belt 206 longitudinally adjacent each of the folding plows 234 are connected to apply glue-setting forces transversely against the downwardly folded marginal flanges. Each unit 244 includes a first pressure memher or roller 245 pivoted on an axis 243 perpendicular to the direction in which the glue-setting force is applied. The pivot 248 for the roller 246 may be secured in a bifurcated frame 250 pivotally mounted to the main framework 202 of the machine to enable the roller pressure member 246 to partake of limited transverse motion relative to the cartons path. The frame 250 is biased by a compression spring to normally urge the roller pressure member 246 to the inward limit of its transverse motion. Another pressure member taking the form of a bar 252 is located adjacent the cartons path of travel on each side of the conveyor to hold each of the glued flanges inwardly.

The carton closing machine illustrated in FIGS. 11-15 further includes a pair of transversely spaced means 254 connected to supply reaction forces to prevent transversely inward flexing of the side walls 16 and 1 8 while the glue-setting forces are being applied by the arrangements 244. Each means advisably includes a V belt 256 trained about an idler pulley 258 and a drive pulley 260. Each idler pulley 253 is journaled in an inverted U frame 262 located above the longitudinal path followed by cartons passing through the machine. Each drive pulley 269 is likewise jo-urnaled in the inverted U frame 262 at the other end thereof. A plurality of rollers 264 each secured as at 266 in the lower portion of the sides of the inverted U frame 262 are adapted to position the lower reach of each V belt 256 so that it engages the upper surface of the planar lids 26 adjacent the fold-down hinge lines 32, 34 with a force suflicient to flex the upper or horizontal surface of the lid slightly downward immediately adjacent or inside the upper portion of the side walls 16 and 18, as shown in the drawings. The presence of the lid portion pressing downwardly behind the upper portion of the side walls serves as a reaction force to resist the tendency of the glue-setting rollers 246 to flex the side walls 16 and 18 transversely inward.

In operation, the carton closing arrangement of this invention illustrated in FIGS. 11-15 may be driven continuously by a motivating arrangement powered by the electric motor. The glue applying wheels 242 and the lid engaging belts 256 continue to run whether or not cartons are passing through the machine. Accordingly, the machine 209 is suitable for mass production carton closing operations in an egg packaging or other carton filling operation in the same manner as the previously described machine 35. To describe the operation of the various components of the closing machine described above in detail, the following description will trace the movement of one carton through the machine.

First, a carton container portion 12 filled with articles such as eggs is fed to the main conveyor means 204 at the entrance of the machine. The carton has no lid attached at this point. The container portion is moved by the conveyor belt 206 into the escapement mechanism or gate 212. When the escapernent mechanism is moved to its open or non-blocking position the carton container portion 12 is free to travel along the conveyor belt 256 to the stop arm 214 located longitudinally adjacent the escapement mechanism. In the open position, the escapement mechanism prevents the next container portion from traveling along the belt 266. Thereafter, the mechanism returns to its closed position and the next container portion moves along the conveyor to the position previously occupied by the released container.

When the stop arm 214 moves to its open or transversely outward position, one of the pusher elements 218 engages the rear end wall 20 of the carton container portion 12 to assist the conveyor belt 206 in moving the container from the stop arm through the remainder of the machinery. As the container passes beyond the stop arm 214 the pusher element 218 engages a planar lid 26 dispensed and supported beneath the lid hopper 239 by the lid positioner 232. The pusher element 218 functions to maintain the assembled carton and lid in correct alignment and proper registry from the moment of contact with the rear edge of the dispensed lid.

Thereafter, the assembled carton 10 is conveyed by the belt 266 and the pusher 218 past the glue applying arrangements 236. The transversely extending marginal flanges 28 and 30 are guided by the downwardly inclined entrance portions of the folding plows 234 across the upper surfaces of the rotating glue applicator wheels 242. This deposits glue on the lower surface of each marginal flange in a longitudinal pattern which, with smooth surface wheels, may comprise continuous longitudinal beads of glue.

As the leading ends of the marginal flanges 28 and 39 pass beyond the glue applying arrangements 236 with a bead of glue on the lower surface of each flange, the upper surface of the flanges engage beneath the extended portions of the stationary folding plows 234. The plows rotate the flanges 28 and 30 about their respective longitudinal hinge lines 32 and 34 so that the flanges are positioned against the upper portions of the side walls 16 and 18 of the carton container portion 12.

As the carton 1B is passing the folding plows 234, the planar portion of the lid 26 comes beneath the lid engaging V belts 256 of the reaction force supply means 254. As explained above, the V belts are positioned at a fixed height correlated with the height of the side walls 16 and 18 of the container 12 to flex the upper planar surface slightly downward immediately inside the upper portions of side walls 16 and 18. This provides reaction forces to resist the glue-setting forces applied by the transversely spaced rollers 246 at the following station.

As the carton passes beyond the flange folding plows 234, the folded flanges are conveyed past the transversely spaced glue-setting force applying units 244. Here, compression springs urge the rollers 246 against the marginal flanges 28 and 30 with glue-setting forces sufiicient to spread the glue, and the bars 252 maintain glue-setting forces sufficient to hold the glued members in contact to securely bond each flange to the upper pop-tion of each side wall of the container portion 12. As noted above, the V belts 256 act to prevent inward flexing of the side walls, which flexing would otherwise tend to dam-age the eggs or other articles in the carton.

Finally, the closed and glued carton is transported by the conveyor belt 206 in the exit end of the machine.

Although in both disclosed embodiments of the inven tion the glue setting forces are applied by roller equipped and spring loaded units, it will be appreciated that sta- 't-ionary pressure units such as properly positioned plows or bars accomplishing equivalent functions may be sub stituted in the discretion of the machine designer. Similarly, the V belts which engage the planar portions of the lids to provide reaction forces may be replaced by longi' tudinally extending bars or presser elements positioned to engage the lids and supported by suitable bracing means on the frame to apply a force sufficient to flex the lids slightly downwardly immediately adjacent the inside of the upper portion of the side Walls. Also, the glue applicators which apply glue in a longitudinal pattern to the zone where the flanges lie against the side walls may be arranged to apply a ribbon of glue to the side wall instead of the flange, or to both, as desired.

Thus, carton closing arrangements have been disclosed which properly position lids across the tops of the side walls of container portions of cartons, and thereafter apply glue in a longitudinal pattern to the zone where down- Wardly folded flanges of the lid will contact the side walls. More-over, the arrangements include means for supplying reaction forces to prevent laterally inward flexing of the side walls in response to glue-settin g forces applied laterally to the outer edge of the flanges which militates against breakage of the carton contents.

While the above described embodiments constitute a preferred mode of practicing this invention, other em- 1 1 bodiments and equivalents may be resorted to Within the scope of the actual invention.

What is claimed is:

1. An arrangement for closing flexible cartons having trough-shaped container portions including bottom walls attached to upstanding side walls and generally planar flexible lids positionable across the tops of the side walls and including marginal flanges adapted to be folded downwardly to lie against the outside of the upper portion of the side Walls, the arrangement comprising a frame, conveyor means on the frame to engage bot-tom walls of cont-aine-r portions for moving them along a longitudinal path past spaced closing means, the closing means including means .on the frame to position lids across the tops of the side walls with the marginal flanges protruding laterally beyond the side walls, means on the frame to apply glue in a longitudinal pattern to the zone where the downwardly folded flanges lie against the side walls, means on the frame to fold the marginal flanges from their laterally protruding position to their downwardly folded position where they lie against the side walls, means on the frame to apply glue-setting forces laterally against the downwardly folded marginal flanges, a longitudinally extending member positioned to engage the upper surface of the generally planar lids adjacent the folded down marginal flanges, and means to apply a force to the longitudinally extending member sufficient to flex the lids slightly downwardly immediately adjacent the inside of the upper portion of the side walls whereby the downwardly flexed portion of the lids supplies reaction forces to prevent lateral inward flexing of the side Walls while the glue-setting forces are being applied.

2. An arrangement for closing flexible cartons as in claim 1 wherein the longitudinally extending member comprises a reach of a belt conveyor adapted to travel at the speed of the passing carton.

3. An arrangement for closing flexible cartons as in claim 2 wherein the reach of the conveyor belt is trained about a plurality of roller positioning devices one of which i s power driven to generate a surface speed of the reach comparable to the speed of the conveyor means which is connected to engage bottom walls of container portions.

4. An arrangement for closing flexible cartons as in claim 1 wherein the means for applying glue-setting forces comprises a pressure member mounted for limited lateral motion, and yieldab-le biasing means to normally urge the pressure member to the laterally inward extent of its limited motion.

5. An arrangement for closing flexible cartons as in claim 4 wherein the pressure member comprises a roller arrangement mounted for free rotation on an axis positioned generally perpendicular to the direction in which the glue-setting forces are applied.

6. An arrangement for closing flexible cartons as in claim 1 wherein the means for applying glue in a longitudinal pattern comprises a glue applying head positioned to deposit a continuous ribbon of glue on the lower surface of laterally protruding marginal flanges.

7. An arrangement for closing flexible cartons as in claim 1 wherein the generally planar lids are pre-secured to the upper portion of the side walls on one side of the container portions and wherein the means for positioning lids across the tops of the side walls includes a stationary folding plow positioned to fold the lids about longitudinal hinge lines adjacent the pre-secured portion of the lids.

8. An arrangement for closing flexible cartons as in claim 7 further including means to insure positive frictional drive engagement between the bottom walls of container portions and the conveyor means which engages them and moves them along the longitudinal path.

9. An arrangement for closing flexible cartons as in claim 8 where-in the means to insure positive frictional drive engagement comprises a belt conveyor having a reach engaging the upper surface of the planar lids adjacent the side walls to which the lids are pre-secured.

It). An arrangement for closing flexible cartons as in claim 9 wherein the reach of the belt conveyor is forced downwardly against the planar lids by means of a backing arrangement, the backing arrangement being yieldably mounted for limited upward travel to compensate for carton tolerances in the dimension between the bottom walls of the container portions and the longitudinal hinge lines of the pre-secured lids.

11. A method for closing flexible car-tons having troughshaped container portions including bottom walls attached to upstanding side walls and generally planar flexible lids position-able across the tops of the side walls and including margin-a1 flanges adapted to be folded downwardly to lie against the outside of the upper portion of the side walls, comprising the steps of positioning lids across the tops of the side walls with the marginal flanges protruding laterally beyond the side walls, applying glue in a longitudinal pattern to the zone where the downwardly folded flaps lie against the side walls, fol-ding the marginal flanges from their laterally protruding position to their downwardly folded position where they lie against the side walls, applying glue-setting forces laterally against the downwardly folded marginal flanges and simultaneously applying a force to the upper surface of the generally planar lids adjacent the folded down marginal flanges suflicient to flex the lids slightly downwardly immediately adjacent the inside of the upper portion of the side walls whereby the downwardly flexed portion of the lids prevents lateral inward flexing of the side walls while the glue-setting forces are being applied.

No references cited.

TRAVIS S. MCGEHEE, Primary Exat'niner. 

